With the abundance of postings on fly specking, a segment of collecting that I generally avoid, I went back into the stock books and pulled these examples out for those that enjoy it.
Here are some examples of Scott #707 – 'Broken E' Plate Flaw. It occurs on Plate Number 20772 UR stamp number 8



We can tell this is a legitimate plate flaw since it occurs on many stamps, I do not have the only one is existence. It is listed in major catalogs although without a value. I cannot find any recent sales for this items; but in no way does this mean that I am now wealthy. It more likely means that no one really cares much about such a minor variety and as such when it does come to market it doesn't bring much additional value.
Here are some examples of the Scott #712 double transfer error. It occurs on Plate Numbers 20563 UL stamp 1 or 20564 LL stamp 91.


Note; click on images for high resolution
We know it is legitimate since it too is repeated across many sheets of stamps of the printing. Many, many eyes have been put on these stamps since they were issued in 1932 and other examples exist. It is also listed in major catalogs and this too does not have a value assigned to it. The value? Not much, a subtle double transfer on a issue that few people specialize in or care about results in little increase in value.
don